Hermes Lite 2, Winlink and Vara

A reliable path to WinLink and Vara with HL2 and Thetis.  

I have found a reliable path to WinLink working with HL2 and Thetis.  The Thetis software and virtual cables have too much total audio delay to allow the rapid response required for Winlink (or anything Vara HF for that matter). What I have found is that the HL2-Plus add on board, plus a DigiRig-Mobile, equals success!  This configuration pushes the audio directly through the HL2+ CODEC, bypassing the virtual cables and the inherent delays.

The Hermes Lite 2 Plus add-on board (HL2+) can be found here:   Hermes Lite 2 Plus
and the DigiRig-Mobile can be found here:  Digirig Mobile – digirig

A SignalLink or other rig-audio-interface could be used instead of the DigiRig, I just happened to have one available. I connected the audio cable (PTT+MIC+SPKR) to the Mic and Phones inputs of the HL2+.  Turn off the VAC1, Use USB (upper-side-band vs DIGU) in Thetis. You have to enable MIC in Thetis and set the RX1-AF and MIC gains appropriately. PTT is managed by CAT commands via Thetis.

This solution also addresses the situation where your buddy is running an HL2 — and you cannot connect on VaraC.  As long as one of you is on this setup — you can connect. The combined delays of two stock HL2/Thetis setups will lead to no joy in VaraC though HL2/Thetis/VaraC works well generally. SDR-to-SDR is where the issues arise.

More to come on this in the near future. Hope this helps in the meantime. 73!

WR9R

UPDATE:

After posting this I received this message via io.groups from Ed, KS7ROH:

I found that my solution to fixing Vara was to reduce the buffer latency under the VAC1 tab. I think they’re set to 120 by default. I have mine set to 10 for the RingBuffer and 5 for the PortAudio. Try adjusting this and see if you get better luck. I use VAC as you normally would and have no problems doing VarAC and WinLink after making this change.

Hope the above helps some folks struggling with this.

73,

Ed KS7ROH

I tested Ed’s solution and found that it worked just great! I have been looking for this kind of solution for some time and I am grateful for his input.

Peace and 73,

Larry

WR9R